Tagged cine magnetic resonance imaging with a finite element model can predict the severity of retrosternal adhesions prior to redo cardiac surgery

Yoshioka, Ichiro; Saiki, Yoshikatsu; Ichinose, Azusa; Takase, Kei; Takahashi, Shoki; Ohashi, Toshiro; Sato, Masaaki; Tabayashi, Koichi

doi:10.1016/j.jtcvs.2008.10.036

« Previous Next »The Journal of Thoracic and Cardiovascular Surgery
Volume 137, Issue 4 , Pages 957-962, April 2009

Tagged cine magnetic resonance imaging with a finite element model can predict the severity of retrosternal adhesions prior to redo cardiac surgery

Ichiro Yoshioka, MD, PhD
- Department of Cardiovascular Surgery, Graduate School of Engineering, Tohoku University, Sendai, Japan
Yoshikatsu Saiki, MD, PhD
- Department of Cardiovascular Surgery, Graduate School of Engineering, Tohoku University, Sendai, Japan
- Address for reprints: Yoshikatsu Saiki, MD, PhD, Department of Cardiovascular Surgery, Graduate School of Medicine, Tohoku University, 1-1 Seiryomachi, Aoba-ku, Sendai 980-8574 Japan.
Azusa Ichinose, MD, PhD
- Department of Radiology, Graduate School of Engineering, Tohoku University, Sendai, Japan
Kei Takase, MD, PhD
- Department of Radiology, Graduate School of Engineering, Tohoku University, Sendai, Japan
Shoki Takahashi, MD, PhD
- Department of Radiology, Graduate School of Engineering, Tohoku University, Sendai, Japan
Toshiro Ohashi, PhD
- Department of Bioengineering and Robotics, Graduate School of Engineering, Tohoku University, Sendai, Japan
Masaaki Sato, PhD
- Department of Bioengineering and Robotics, Graduate School of Engineering, Tohoku University, Sendai, Japan
Koichi Tabayashi, MD, PhD
- Department of Cardiovascular Surgery, Graduate School of Engineering, Tohoku University, Sendai, Japan

Received 9 May 2008; received in revised form 15 September 2008; accepted 27 October 2008. published online 23 February 2009.

Objective

Reoperative median sternotomy entails a risk of damaging the heart or great vessels. If the severity of retrosternal adhesion is accurately assessed before sternal re-entry, resternotomy-related complications can be prevented. The purpose of this investigation was to evaluate whether the severity of retrosternal adhesions can be accurately predicted by tagged cine magnetic resonance imaging.

Methods

Thirteen patients who were scheduled to undergo cardiac reoperation were investigated by electrocardiography-gated tagged cine magnetic resonance imaging before sternal re-entry. With the imaging data, the severity of retrosternal adhesion was scored visually on the basis of abnormality in regional myocardial motion and discordance in the tagged signals of the sternum and the myocardium. Also, with the aid of a finite element model, strain at the surface of the right ventricle was calculated on the basis of displacement of the tags on the heart over the cardiac cycle. For comparison, the adhesion severity was scored visually at the time of redo surgery by surgeons who were blinded to the preoperative assessment.

Results

The preoperative adhesion severity score, as determined visually by tagged cine magnetic resonance imaging, was correlated with the intraoperative severity score (correlation coefficient: r = 0.76, P < .01). Mean strain at the surface of the heart, as calculated preoperatively by finite element model analysis, was inversely correlated with the intraoperative adhesion severity score (r = −0.78, P < .01).

Conclusion

Tagged cine magnetic resonance imaging with a finite element model can provide an accurate quantitative assessment of retrosternal adhesions before redo cardiac surgery.

Abbreviations and Acronyms: CT, computed tomography, FOV, field of view, MRI, magnetic resonance imaging, TR/TE, repetition time/echo time

CTSNet classification: 13, 18, 32